Printing telegraph apparatus



Sept. 14, 1943.

A. H. REIBER PRINTING TELEGRAPH APPARATUS Original Filed May 4, 1956 10Sheets-Sheet 2 Zhwentor ALBERT H. REIBER attorney Sept. 14, 1943. A. H.REIBER 2329,65?

PRINTING TELEGRAPH APPARATUS- Original Filed May 4, 1936 10 Sheets-Sheet3 TO MOTOR CONTROL .8 367 MECHANISM FIG. 23

'Jmamtor ALBERT H. REIBER TO "TAPE TRANSMITTER 24 Gttomeg EHH Sept. 14,1943. A. H. REIBER 2,329,652

PRINTING TELEGRAPH APPARATUS Original Filed May 4, 1936 10 Sheets-Sheet4 Zhwentor ALBERT H. REIBER '(Ittomeg p 14, A. H. REIBER 2,329,652

PRINTING TELEGRAPH APPARATUS Original Filed May 4, 1936 10 Sheets-Sheet5 vcuto FIGJS ALBERT .ssa

- Gttomeg p 3- A. H. REIBER 2,329,652

PRINTING TELEGRAPH APPARATUS Original Filed May 4. 1936 10 Sheets-Sheet6 Mum d FIG. 8

3m entor ALBERT H. REIBER (Ittomei;

Sept. 14, 1943. A. H. REIBER PRINTING TELEGRAPH APPARATUS Original FiledMay 4, 1936 10 Sheets-Sheet '7 Inventor ALBERT H. REIBER Original FiledMay 4, 1936 10 Sheets-Sheet 8 FIG. I2

see

Smaentor ALBERT H. REIBER Gttomeg Sept. 14, 1943. REIBER PRINTINGTELEGRAPH APPARATUS Original Filed May 4, 195's 1o Sheets-Sheet 93nnntor ALBERT H. REIBER attorney Sept. 14, 1943. I A. H. REIBER2,329,652

PRINTING TELEGRAPH APPARATUS Original Filed May 4, 1936 10 Sheets-Sheet10 FIG-2| Zmventor ALBERT H. REIBER Patented Sept. 14, 1943 2,329,652PRINTING TELEGRAPH APPARATUS Albert H. Reiber,

Delaware Evanston, 111., assignor to Teletype Corporation, Chicago,111.,

a corporation of Original application May 4, 1936, Serial No.

77,796, now tember 29, 1942.

Patent No. 2,296,874, dated Sep- Divided and this application May 4,1938, Serial N0. 205,926

24 Claims.

This invention relates to printing telegraph apparatus and particularlyto a type wheel printer for recording printed characters in page form.

This application is Serial No, 77,796, filed Reiber, now Patent No. 29,1942.

The principal object of the invention is to endow a type wheel printerwith many of the advantageous faetures of a type bar printer whileretaining the simplicity of construction characteristic of type wheelprinters.

A further object is to provide a type wheel printer having the principaloperating charac teristics of certain commercially used type barprinters so as to be capable of being operated over the same telegraphcircuits and in interconnection with the commercially used type barprinters to record the same message in line for line arrangement andperform the same functions as the type bar printer.

A still further object of the invention is to con-- trol the operationof a cyclic overlap printing telegraph receiving apparatus including atype a division of application May 4, 1936, by Albert H. 2,296,874,granted Sept.

mechanism for feeding an inked ribbon between the type wheel and aprinting platen including means for controlling the direction of feedingof the ribbon, and a movable carriage which carries the paper upon whichprinting is to be eifected.

Heretofore, code disc selectors, for controlling the arrestment of typewheels from which printing is to be efiected during signal reecivingcycles, and having notched discs arranged to cam selected stop pins tounselected position during a code selection changing operation, havebeen controlled by ticker selector mechanisms which include transferlevers carried by a transfer bail and not normally in direct associationwith the settable elements of the ticker selector and code discs. Swordand T-lever selector mechanisms have been employed principally in thecontrol of code bar selector mechanisms having square cut wheel andcontrolling code disc selector unit by a sword and T-lever selectormechanism.

A feature of the invention is to provide, in connection with a sword andT-lever selector mechanism, a locking instrumentality operable directlyupon the T-levers for timing the signal combination transfer operation.

A further feature of the invention is to provide, in connection with asword and T-lever selector mechanism, a power actuated transfer deviceincluding a yieldable element individual to each train of seelctorelements for completing the signal code setting of all of the trains ofselector elements simultaneously.

The invention also features a power actuated transfer bail operated intimed relation to the operation of the receiving distributor havingoppositely extending arms, one of which carries a locking blade whichserves as a lock for the T- levers, and the other of which carriesspring loops through which the transfer operation is affected.

Briefly, the prinicpal elements of the receiving apparatus are aselecting mechanism including a single magnet selector and a code discselector, power driven operating cams controlled from the selectingmechanism, a typewheel and means for stopping it in accordance with theoperation of the code disc selector, cam operated means foreffecting-printing from the type wheel, cam controlled and operatedmechanisms for performing the necessary stunts or functions of theprinter,

, locking blade which the selectable bars may drop individually. In acode bar selector mechanism, including a full complement of selectablebars, none of the code bars is movable when a selectable bar is in analignment of.

selection notches into notches, and therefore, a selectable bar mayserve effectively as a lock on the code bars, to prevent the shifting ofany of the bars during a concur-,

rently running receiving cycle of the sword and T-lever selectormechanism and operating cycle of the selectable bar mechanism.

According to the present invention, the T- levers of the sword andT-lever selector mechanism are at all times in articulation with thecode discs, and the sword levers are normally in engagement with theT-levers. The T-levers have extensions which are presentable on one sideor the other of a locking blade carried by a cyclically operable bail.The bail also carries an arm which mounts a-plurality of U-shape prings,equal in number to the number of sword levers. As the is withdrawn, theU-shaped springs engage the bell crank levers associated with those ofthe sword levers that have been rotated from marking to spacing positionor vice versa, and shift them simultaneously to normal position, thusrocking their associated T-levers and shifting the corresponding codediscs to new selective positions.

Springs which engage the sword lever bell cranks and have sometimesfurnished the sole power for shifting the sword levers, rocking theT-levers and shifting the code bars to new selective positions may,according to the present invention, serve merely to bias the sword leverbell cranks, the ball which carries the locking blade and the U-shapedtransfer springs being new selective condition in the code discselector.

The particular type wheel mechanism disclosed herein is fully describedand claimed in a copending application of Howard L. Krum et 2.1., SerialNo. 77,794, filed May 4, 1936. I

For a more complete understanding of the in vention, reference may behad to the following detailed description, taken in conjunction with theaccompanying drawings in which Fig. 1 is a perspective view of thecombined transmitting and receiving apparatus in accordance with theinvention;

Fig. 2 is a front elevational view of the receiving and printingmechanism;

Fig. 3 is a side elevation of the transmitting and receiving mechanism;

Fig. 4 is a vertical sectional view through the receiving and printingmechanism;

Fig. 5 is a top plan view of the transmitting and receiving mechanism;

Fig. 6 is a detailed plan view of the selecting mechanism and portionsof the carriage mechanism;

Figs. 7 and 8 are respectively, elevational and plan views of the caseshift mechanism;

Fig. 9 is a horizontal sectional view showing the spacing and functionperforming mechanisms;

Fig. 10 is a horizontal sectional view showing details of the spacingmechanism;

Fig. 11 is a horizontal sectional view showing details of the transfermechanism;

Fig. 12 is an exploded view in perspective of the function selecting andperforming mechanisms;

Fig. 13 is a perspective view of the ribbon feed mechanism;

Figs. 14 and 15 are plan views of the ribbon feed mechanism showingdifferent conditions of operation;

Fig. 16 is a vertical sectional view through'the ribbon feed mechanism;

Fig. 17 is a perspective view of the platen carriage showingparticularly paper holding and guiding means;

Fig. 18 is a perspective view of a removable roll holder shown in brokenlines in Fig. 17;

Fig. 19 is a perspective view of a paper guid ing plate;

Fig. 20 is a vertical sectional view through the platen carriage showingthe manner of mounting the plate shown in Fig. 19 upon the carriage;

Fig. '21 is avertical sectional view showing the line feeding mechanism;

Fig. 22 is an elevational view of a modified print hammer operatingmechanism; and

Fig. 23 is a schematic wiring diagram.

Keyboard transmitter 2| which carries a plurality of transmitting cams22. A contact controlling bell crank lever 23 is associated with each ofthe transmitting cams 22. One end of each of the bell crank levers 23 isdisposed in engagement with one spring of a pair of transmitting contactsprings 24 (Fig. 1) and the other end is aligned with a lever 26 whichis controlled by the permutation bars (not shown). In their idlepositions, the transmitting cams 22 maintain the bell crank levers 23 ina position such that all but one of the pairs of transmitting contactsare open, the excepted contact pair being closed for the application of.a stop pulse to the line. Upon the operation of a keylever l8, thepermutation bars and therefore the levers 26 which they control are setpermutatively, whereby certain of the bell crank levers 23 are blockedso that they cannot rotate and others are freed so that they may rotateto allow closing of the associated transmitting. contacts 24 whenpermitted to do so by their associated transmitting cams 22. Thetransmitting cams are so arranged upon the shaft 2| that they releasethe several transmitting contact bell crank levers 23 successively forrotation and thus the transmitting contacts corresponding to theparticular permutation code established by the operated keylever areclosed successively. A locking bail 28 has a cam follower 29 which rideson a cam 3| carried by cam shaft 2|. Bail 28 drops into blockingrelation to the levers 26 after they are set by the permutation bars andprevents disturbance of an established code combination during thetransmission of the corresponding code impulses. Power for driving thetransmitting cam shaft 2| is communicated through a spring loadedclutch- 32 from a gear 33 which is driven through suitable intermediategearing 35 from a gear 4| (Figs. 1 and 2).

The base casting l6 removably supports the foundation for a receivingprinter comprising a vertically extending frame casting 36 and a framecasting 31 secured to the casting 36. The frame casting 36 extends fromfront to rear of the base casting l6 and the casting 31 extendstransversely thereof. The frame casting 36 has secured thereto bearingblocks 38 which rotatably support a shaft 39. Shaft 39 has securedthereto a gear 4| (Figs. 1 and 2) which is driven by a spiral gear 42(Fig, 4) which is mounted on the rotor shaft of motor 34 and constitutesthe main driving gear of the receiving printer as well as of thetransmitting mechanism. The shaft 39 actuates the selector mechanism ofthe receiving printer and also the operation performing cams.

The driving gear 42 (Fig. 4) also meshes with a gear 43 which is mountedon a shaft 44 and is operativcly connected thereto through a frictionclutch 46. Shaft 44 is journalled in a code disc selector mechanismindicated generally by the reference numeral 41 (Fig. 3) which isremovably supported on the frame member 36.

Selecting mechanism At the top of frame member 36 there is mounted asingle magnet selector mechanism which is generally similar to theselector disclosed in U. S. Patent 1,937,376, granted-November 28, 1933,to Walter J. Zenner. The selector mechanism (Fig. 6) comprises a set ofselectbr elements in the form of thin, flat fingers 5| arranged insuperposed relation between guide plates 52. The selector fingers 5|equal in number the signalling elements in the code on which thereceiving printer operates. code is employed, there will be five of theselector fingers 5!, whereas a six-unit code will re- Thus, if afive-unit quire six selector fingers. The guide plates 52 are mounted onstuds 53 secured to the selector mounting plate 54 and are spaced bywashers (not shown). The circular left ends 56 of selector fingersengage corresponding sockets of thin, flat bell crank levers 51 pivotedon a common shaft 58. Individualsprings 59 bias the bell cranks 51 intheir clockwise direction whereby the selector fingers 5| are urgedrightwardly. The pointed ends 6| of bell crank levers 51 are thusmaintained in contact with a cam barrel 62 which is mounted on shaft 39and is driven thereby through friction discs, indicated at 63 (Fig. 4).

Cam barrel 62 is provided with a helically arranged series of camprojections 64 (Fig. 6), one for each of the bell cranks 51, whichrotate the bell cranks 51 in succession and thus draw the selectorfingers 5| leftwardly successively as the cam barrel 62 is rotated.longitudinal movement, the selector fingers have a laterally swingingmovement between a pair of studs 66. l

The setting of any selector finger 5| either to its clockwise orcounterclockwise position is determined by the electro-magnet 61 whichis mounted on the mounting plate 54 and which is provided with armature68 fixed to a flutted lever 69 which is pivoted at 1| to a frame carriedby the supportin plate 54. Mounted on a pivot 12 adjacent to and incooperative relation with the flutter lever 69 is a selector lever 13.Lever 13 terminates in a T-shaped' portion 14 having downwardl extendingarms 16 (Fig. 1) which constitute abutments which cooperate with arms 11(Fig. 6) on the left ends of the selector fingers 5| and act to positionthe latter in extreme clockwise or extreme counterclockwise positions.Theseveral fingers 5| act through a. corresponding number of levers 18arranged between the guide plates 52 and pivotally mounted on a stud 19to position transfer bell crank levers 8|, pivoted at 85, which havedisc portions 82 engaging sockets in levers 18.

As previously stated, each selector finger 5| is shifted clockwise orcounterclockwise by having one or the other of its arms 11 drawn againstone or the other of the abutments 16 of the T-shaped portion 14 ofselector lever 13. The selector lever 13 is connected by a spring 83 toan arm 84 of the flutter lever 69 and the minimum distance between thelevers 69 and 13 is determined by an abutment screw 86. The flutterlever 69 has a portion which follows a flutter cam 81 (Figs. 2 and 4)included in the cam barrel assembly 62.

As the signal impulses are received over the telegraph line, theelectromagnet 61 is energized and deenergized depending upon the natureof such impulses. During thereception of a set of impulses constitutinga signal, the cam barrel 62 is rotated, flutter lever 69 follows fiuttercam 81, and armature 68 is moved cyclically into engagement with itspole face. If the armature 68 is then held due to the presence of anenergizing impulse through the winding of its electromagnet connected inthe line, the flutter lever 69 will be prevented from following thecontour of the fiutter cam 81. The abutment screw 86 and spring 83 causethe selector lever 13 to follow the motions of the flutter lever 69 sothat when the levers are moved counterclockwise, one of the abutments 16of selector lever 13 is moved into alignment with one set of arms 11 ofthe selector fingers 5| and when the levers are rotated to their Inaddition tothe a set of extreme clockwise positions, the other abutment16 is moved into alignment with the other set of arms 11. The severalcams 64 on the cam barrel 62 are so positioned with respect to thefiutter cam 81 that the selector fingers 5| are drawn leftwardly insynchronism with the signallin impulses received by the selector magnet61 so that a selector finger 5| will be moved from a positioncorresponding to a spacing signal to a position corresponding to amarking signal only if the armature 68, after being rotated intoengagement with its pole face by flutter cam 81, is held by theelectromagnet as the selector finger 5| is drawn leftwardly by itsassociated bell crank lever 51 and will not be so shifted as a result ofmere movement of the armature 68 as the flutter lever 69 follows a highportion of fiutter cam 81. 'A cam operated lock lever 88 locks andreleases selector lever 13 at proper intervals under control of a cam 89on the cam barrel 62.

Thetransfer bell crank levers 8| are connected by socket connections tothe code discs of a code disc selector mechanism which, as previouslymentioned, is designated generally by the reference numeral 41. Theselector mechanism 41 includes code discs 9| equal in number to thenumber of selector fingers 5|, and each of the discs is supported so asto be rotatably responsive to the'transfer bell crank lever 8| to whichit is articulated. The discs 9| have their edges notched permutativelyso that for each permutative setting of the discs a single completealignment of notches of the several discs will be effected.

The code disc selector mechanism 41 has plates 92 and 93 (Fig. 4)disposed respectively above and below the code discs 9| and a plate 94disposed below and at some distance from the plate 93. The three plates92, 93, and 94 have radially arranged slots equi-distantly spaced, theslots corresponding in number and positions to the permutative alignmentof the notches in the code discs 9|. A selectable stop pin 96 isdisposed in each vertical alignment of slots in the discs 92, 93,

and 94 and each pin has a portion extending below the disc 94, whichportion is eyelet-shaped, and a straight portion extending above thedisc 92. A garter spring 91 surrounds all of the stop pins 96 andretains them properly seated in the disc 94.

Each of the pins 96 carries anti-friction rolls 95 (Figs. 4 and 6) equalin number to and in alignment with the code discs 9| With anypermutative disposition of the code discs 9| an alignment of notcheswill be presented opposite the antifriction rolls carried by one of thestop pins 96. The stop pin opposite which the notches are aligned pivotsabout the inner limit of the slot in the plate 94 so that its upper endmoves toward the type wheel shaft 44 in a direction radially of saidshaft as the anti-friction rolls 95 become seated in the alignment ofnotches in the code v discs. Only one of the stop pins 96 can beselected at a particular time due to the fact that there cannot be twoalignments of code disc notches simultaneously.

The type wheel shaft 44 carries in fixed relation thereto a stop arm 98,the outer end of which clears unselected stop pins 96 but is blocked bya selected stop pin and is prevented from further rotation until theselected pin has been cammed outwardly by one or more of the code discsdue to a change in their permutative arrangement. A leaf spring 99 (Fig.6) carried by the stop arm 98 and the end of the leaf spring 99 passesover the top of any stop pin 96 that is selected and drops ahead of thepin when the arm 98 is stopped,

Transfer mechanism The shifting of the code discs 9I to establishsuccessive selections of the stop pins 96 is effected through the mediumof a power actuated trans fer bail I02 (Figs. 1, 2, 3, 6, and 11). Theba l I02 is pivoted on a shaft I03 and has a lever I04 adjustablyconnected thereto by screw I05. The lever I04 carries a cam followerroller I06 which rides against a cam I01. The bail I02 has at its upperend a vertically extending arm I08 to which is secured by bolts I09 aU-shaped extension III (Fig. 6). The arm I08 and the opposite sideportion of the extension III are provided with rectangular apertureswhich receive U- shaped springs II2. One arm of each of the springs II2extends through the aperture in the arm I08 of transfer bail I02 andterminates in al gnment with one of the bell crank levers 51. The otherarm of each of the springs II2 terminates in the aperture in the arm I08and is confined there by that arm of the U-shaped extension I II whichis secured by the screw I09 and which partially covers the aperture inarm I08. The springs II2 are under tension in the aperture-in thevertical arm I08.

The springs II2 serve as individual yielding operating connectionsbetween the transfer bail I02 and the several bell crank levers 51. Whenthe transfer bail I02 is rocked in a clockwise direction by cam I01, theends of the springs H2 engage the bell crank levers 51 and rock themclockwise and the bell crank levers in turn shift the selector fingersrightwardly. The selector fingers 5| rock the levers 18 clockwise orcounterclockwise, depending upon the positions into which the fingers 5|have been moved through the action of the selector magnet 61, selectorlever 13, and bell crank 51. As previously described, shifting of thelevers 18 causes corresponding shifting of the transfer bell cranklevers 8| which are articulated to the code discs 9I so that permutativearrangements of the code discs in accordance with signals received bythe selector magnet 61 are set up when the transfer bail I02 is actuatedin a clockwise direction. Springs 59 bias the bell crank levers 51 inclockwise direction, as previously described, and while the springs maybe of sufficient tension to shift selector fingers 5|, the levers 18,transfer levers 8|, and code discs 9|, it has been found desirable notto rely on the springs to effect the transfer of selections to the codediscs, and to this end a locking bar has been provided to prevent thesprings from effecting such transfer at all times except when thetransfer ball is to be operated.

The transfer bail is provided with an extension arm II3 which terminatesin a knife-edge H4. The levers 18 are provided with extensions IIS whichterminate beyond the position occupied by the knife-edge II4 when thetransfer bail I02 is in its extreme counterclockwise position. The

2,329,652 precedes the stop arm 98 as the shaft 44 rotates knife-edgeII4 thus serves when in looking position to restrain the levers 18 frombeing moved by the springs 59. Since the extension arm II 3 is carriedby the transfer bail I02 it is withdrawn to a position which clears theends II8 of the levers 18 when the transfer bail is rocked in aclockwise direction and at this time the code discs are shifted by thecombined action of the transfer bail I 02 operating through springs H2and the springs 59. Arm II3 returns to locking position when thetransfer bail I02 is restored to its normal or unoperated position.

Type wheel The type wheel shaft 44 has a reduced portion I2I at theupper end thereof which provides a shoulder I22 (Fig. 4). A hub I23 isjournalled on the reduced portion I2I of shaft 44 and is slidablethereon. At its upper end the hub I23 carries a disc I24 to which issecured an annular type wheel frame I26. The frame I25 has slots inradial arrangement equally spaced therearound, and in each of the slotsupper and lower type pallets I21 are slidably disposed. The type palletsI 21 are arranged in upper and lower annular rows, one row of which maycarry any desired group of characters such as letters and the other ofwhich may carry other characters such as figures and punctuation marks.The type pallets comprise type faces I28 to which are secured thinshanks I 29 which extend inwardly and radially of the type wheelstructure within the radial slots thereof. The shanks of each annularrow of type pallets are notched to receive a garter spring I3I whichbiases all of the type pallets of an annular row to their innermostpositions with the type faces I20 disposed about the periphery of theslotted frame I26. An annular ring I32 is fioatingly disposed in thenotches in both annular rows of type pallets and prevents the typepallets from accidental displacement from the type wheel structure dueto centrifugal force in the event that one of the garter springs I3Ishould break. At one portion of its periph ery, the type wheel structurehas no type pallets and at that point the disc I24 and frame I26 areprovided with recesses in which is disposed a perpendicular portion I33of a type wheel driving arm I34 which is adjustably secured by screwsI30 to anarm I35 which is carried by the type whee1 shaft 44 at the topthereof in fixed relation to the shaft to be driven thereby. Theadjustability between the arms I34 and I35 is angular.

The type wheel structure is slidahle longitudinally of the type wheelshaft to bring either of the two rows of type pallets into printingalignment with the printing platen, the shifting of the structure beingaccomplished by a sliding movement of the hub I23 with respect to thetype wheel shaft 44 produced by mechanism to be described hereinafter.As the type wheel is shifted, the recesses in which the perpendicularportion I33 of driving arm I34 is disposed slide upon the portion I33and driving relation between the type wheel shaft and the type Wheel ismaintained. A printing hammer I35 is pivotally mounted on screws I31threaded into the stationary bracket I25 (Fig. 3) and has its head inalignment with the printing position so that it is disposed behind theshank of the type pallet of either of the annular rows of type pallets,depending upon whether the type wheel is in its upper or lower position.The printing hammer I38 has integral therewith a bail portion H9 atmovement thereof.

- the pawl to travel rlage I as it travels into its extreme righttheopposite end of which is integrally formed a leverarm II1 (Figs. 1 and3) which carries an impact receiving member I38. .A limit screw II8limits the operative movement of lever arm H1. The lever arm H1 isactuated by a striker member to be described later. The operativemovement of the print hammer I36 is a sudden clockwise rotation asviewed in Fig. 4, whereby the type pallet which is aligned withthe printhammer at the moment is driven outwardly and radially of the type wheelstructure into engagement with the printing platen I39. A stop bar I20mounted on top the bracket I25 projects into the path of the h mmer I36and limits the Carriage mechanism The printing platen I39 is rotatablymounted in end plates I40 of a reciprocating carriage I4I (Fig. 1). Thecarriage MI is' supported in adjustable rails I42 at the top of the mainframe member 31. Anti-friction balls I43 (Fig. 4) are disposed betweenthe carriage MI and the rails I42 and provide free movement of thecarriage with respect to its supporting rails. The rotatable platen isprovided with a feed ratchet I46 (Fig. 2) with which there cooperates afeed pawl I41 (Fig. 21).

The platen feeding pawl is articulated to a lever I49 (Fig. 21) that isfixed to a rock shaft I50. The rock shaft I50 is rotatably journalled inthe carriage MI and has fixed thereto at a point substantially midwaybetween the ends of the carriage I4I an operating lever I60. The leverI49, rock shaft I50, and operating lever I60 are biasedcounterclockwiseby a spring I65. Feeding of the ratchet I46 in the direction indicatedby the arrow is effected by clockwise rotation of operating lever I60,by a power actuated bail to be described later, against the ten- 1 sionof spring I65, which subsequently acts to reciprocate the pawl I41 topick up the next tooth or teeth for the next line feeding operation. Alever I10, pivoted on the carriage end plate I40, provides two abutmentsfor deflecting the pawl at difierent points in its ,ravel to idle orunoperated position to establish single or doubleline spacing. When thelever is in the position shown in dotted line, it permits sufficientlyfar in engagement with the ratchet I46 to pick up two teeth, whereas ifthe lever is in the full line position the pawl is deflected from theratchet and is permitted, when it operates,, to pickup only one tooth.An adjustable eccentric I15 is mounted on the carriage end plate I40 andis disposed in thepath o a camming lug I on the pawl I41 for wedging thepawl against the ratchet to prevent over-travel of the ratchet andplaten. A spring biased jockey roll I90 bears against the ratchet I46and controls the positioning of the platen I39.

The carriage MI is moved to its right-hand position by a belt I5I (Fig.2), which has one end connected to a drum I52 which contains a spiralspring by which the drum is urged to rotate in a clockwise direction andwhich has its other end connected to a. pin I53 (Figs. 3 and 6) carriedby the carriage MI. The carriage MI is moved leftwardly by spacingmechanism to be described hereinafter against the action of the spiralspring. A lever I56 pivoted at I51 (Fig. 3) has one end articulated tothe plunger rod I58 of a dashpot I59 and has its other end positioned tobe engaged by the carhand position by theaction of the spiral spring.

With this arrangement, the return of the carriage to its extremeright-hand position is cushioned by the dashpot I56. Stop screws I54threadedly engage the carriage supporting portion I41 of the framecasting 31 at opposite ends of said portion, and the inner ends of thestop screws are disposed in the path of a bracket I45 mounted on thecarriage MI. The screws I54 limit the movement of the carriage in bothdirections of travel.

Ribbon mechanism I62 designates a plate which is the foundation of theentire ribbon feed mechanism and which is in turn supported on theprinter by means of posts I63 so that the complete ribbon feed mechanismis removable as a unit.

The plate I62 carries arcuate ribbon guide band I64 which guides theribbon around the type wheel assembly IOI and which is provided with anaperture I66. through which the type pallets may strike against thepaper, upon which characters. are to be recorded, with the ink ribboninterposed between the type pallets and the paper whereby a characteris. imprinted upon thqspaper. Ribbon spool supporting pins I61 arejournalled in the side arms of the plate I62 and each pin has securedthereto above the plate I62 :3. disc I68 and at the lower end of the pinbelow the plate I62 a ratchet wheel I69 which may be rotated by means ofa pawl to cause the positive rotation of the pin I61 and disc I68. Eachof the discs I68 carries a pin I1I which engages a ribbon spool I12 tocause the spool to be driven when the ratchet I68 is positively rotatedby its operating pawl.

The plate I62 carries a pivot pin I13 on which, below the plate I62,'-are pivoted two levers, one of which is designated generally by thereference numeral I14, the other of which is designated generally by thenumeral I16. The lever I14 has oppositely extended symmetrical arms I11at the outer ends of which are portions I18 formed perpendicular to thearms I11 and bifurcated. The path of the ink ribbon, as it passes fromone spool to another, is through the bifurcations in the perpendicularportions I18 of the arms I11. The lever I14 also has an arm I19extending away from the arms I11 on the line of a bisector of the anglebetween the arms I11. This arm I19 is widened at its outer end as shownat I8I and an additional arm I82 which is pointed at its outer endcooperates with a spring I80 to serve as a jockey to maintain the leverI14 in either of the two positions to which it may be shifted. Lever I16has the general contour of .a bell crank lever, one arm I84 of which hasat its outer end shoulders I86 disposed in the plane of the ratchetwheels I69 to serve as a, retaining pawl for either of the ratchetwheels to prevent the wheel from slipping back as it is advanced by thefeed pawl. The arm I84 of the bell crank lever I16 is providedintermediate its ends with an aperture I81 which is substantiallyparallelogrammatic and which may be described roughly as diamond shaped.Manifestly, the lever I16 is limited in movement by the two ratchetwheels I69. The other arm I88 of the bell crank lever I16 supports oneend of the tension spring I89, the other end of which engages a springpost I9I which is so positioned that as the lever I16 shifts fromengagement with one ratchet wheel to engagement with the other, thespring I89 is carried across the pivot pin I13 and serves as anover-center device for the lever I16.

An operating lever I 92 for the ribbon feed mechanism is pivoted toplate I62 at I93 and carries at its inner end a pivot pin I 94 on whichis pivotally mounted the ratchet feed pawl indicated generally by thereference numeral I96. The feed pawl I96 is U-shaped and both arms aremounted on the pivot pin I92. The upper arm I91 has upwardly extendingabutments I98, the distance between which is somewhat greater than thedistance across the widened end I8I of the arm I19 of lever I14. Theupwardly turned abutments I98 extend at least as high as the outer endof arm I19, so that they may engage the widened end thereof in a mannerto be described. The lower arm I99 of the feed pawl I96 is formed at itsouter end with ratchet wheel engaging portions 20I disposed in the planeof the ratchet wheels I69. Intermediate the ratchet engaging portionthere is a depending pin 202 which extends into the diamondshapedaperture I 81 in the lever I16. A floating link 203 has one end engagingthe upper end of pin 202 and the other end engaged by a tension spring204 which is connected to the plate I62. The spring 204 and link 203serve as an over-center device for the feed pawl I96 and bias theoperating arm I92, by which the stepping pawl is carried, to theunoperated position. A power actuated lever 206 carrying a link 205which engages the ribbon feed operating lever I92 cyclically operatesthe lever by rotating it clockwise in opposition to the tension ofspring 204. Lever 206 is pivotally mounted at 208 (Fig. 1) and isactuated by lever arm 249, which, as will appear subsequently, is oper-.ated by a cam. Leaf springs 201 frictionally engage ratchet wheels I 69and place sufliclent drag on the spool from which the ribbon is beingdrawn to insure tight winding of the ribbon on the other spool.

Referring particularly to Fig. 14 for a description of the operation ofthe ribbon feeding mechanism, it will be noted that pawl I96 has beenpulled into engagement with the left-hand ratchet wheel I69 by theover-center device comprising the link 208 and spring 204. position theright-hand abutment I98 is somewhat nearer to the rear of the mechanismthan is the left-hand abutment. It will also be noted that the springI89 is in front 01' the pivot pin I13 and urges the arm I84 of retainingpawi lever I16 into engagement with the left-hand ratchet wheel I 69.The operating lever I92 is periodically rotated clockwise by theoperating bail 206 and in being so rotated, it moves the ratchet feedpawl I96 rearwardly of the typing unit, and the pawl, being inengagement with the left-hand ratchet wheel I69, rotates itcounterclockwise. Upon restoration of the lever I92 pawl I 96 is broughtinto engagement with the next tooth of the ratchet wheel preparatory tothe next ribbon feeding operation. As the ratchto its unoperatedposition, the

.forward wall of the retaining pawl lever et wheel is rotated end of armI84 oi.

pawl I96 as the latter returns to its unoperated position. It may be thefeeding of the left-hand ratchet wheel I69 takes place, the pin 202carried by the feed pawl I 96 moves within the, diamond-shaped aperturein the retaining pawl arm I64 adjacent to the left-hand aperture withoutaffecting the position 01' the pawl arm.

The direction of feeding of alignment with the right-hand abutment. Thisoperation does not in itself transfer the feeding operation from theleft-hand ratchet I 69 to the right-hand ratchet. The transfer of thefeeding operation will occur, however, upon the next operation of theoperating lever I92 by bail 206. When the lever I92 is gagement with theright-hand ratchet I 69 with the assistance 01 the over-center link 203and spring 204. The bell crank lever I16 will be ribbons of the ribbonitself with the of the lever I14.

the moving ribbon a distance suilicient to block one of the abutmentsI98 of the pawl I96, the ratchet feeding will be transferred upon thenext operation of the operating lever in the manner described in theforegoing paragraph. It will be noted that due to the previouslydescribed dragging action 01' the leaf spring 201, which causes tightwinding of the ribbon, there is no slack to be taken up when theobstruction in the ribbon encounters the perpendicular arm I10 andplaces the additional load of the lever 111 on the ribbon. The

ribbon will thus continue to move and to be to be shifted by the poweroperated actuating lever upon the next operation thereof.

Operating cams The operation ofthe ribbon feed bail 266, the printhammer lever 111, and the transfer bail 102 is effected by operatingcams mounted on the shaft 39 above the gear- 41 (Fig. 4). The operatingcams are assembled in fixed relation with respect to each other on asleeve which is mounted on shaft 39 and which has associated therewiththe driven portion of a spring loaded tooth clutch 211, the drivingportion of which is keyed or staked to shaft 39. A clutch throw-outlever 212 pivotally mounted on shaft 213 is spring biased intoengagement with the driven portion of the clutch 211 and has an arm 214(Fig. 2) disposed in the path of a cam projection 210 (Figs. 1 and 6)included on the selector cam barrel 62. With this arrangement, at .agiven point in the cycle of operation of the cam barrel 62, camprojection 210 rocks the arm 214 which withdraws the clutch throw-outlever 212 from restraining engagement with the driven portion of theclutch 21 1 and permits driving engagement to be established between theshaft 39 and the cams mounted thereon.

The uppermost of the cams is a channel or box cam designated by thereference numeral 216, the cam groove 211 (Fig, 9) of which receives thefollower roller 218 rotatably mounted on a bell crank lever 219 rockablymounted on the pivot shaft 221. ticulated at 222 to a bar 223 to whichit is arranged to impart a reciprocatory motion due to the fact that thecam groove 21'! has one offset 224 which, when encountered by thefollower roll 218, causes the lever 219 to rock counterclockwise upon'its mounting shaft 221 and in this way the bar 223 is reciprocatedrearwardly of the typing unit. A lever 226 is also rockably mounted upontheshaft 221 and is secured at its forward end to the cam operated bellcrank 219 by a clamping bolt 221 which passes through a. slot 228 in thebell crank 219. The slot 226 provides adjustability in the clampingtogether of the levers 219 and 226. The lever 226 is effective in theconditioning of functions when they are selected, and its operation willbe described later,

The bar 223 carries intermediate its ends an eccentrically mountedabutment 230 against which abuts the operating arm 229 of a strikermember or hammer 231 pivotally mounted at 232 (Fig. 1). The bar 223 hasa depending lug 220, and a tension spring 225 has one end connected tothe lug 22D and the other end connected to the operating arm 229 ofstriker 231. The striker member 231 is provided at its upper end with amassive head 233 which describes an are as the hammer 231 is rocked andwhich delivers a sharp blow to an impact receiving abutment 138 ofresilient material, such as rubber or leather, carried by the printhammer operating lever arm 111. As indicated in Fig. 9, the offset 224in the groove 211 of cam 216 is very abrupt and very The bell cranklever 219 is arshort, so that the reciprocation of bar 223 to itsrearmost position -is very rapid and thus the blow impartedby thestriker member 231 to the sharp.

print hammer operating lever arm 1111s very stances which will bedescribed later.

The cam which is directly beneath the cam 216 is designated by thereference numeral 101 (Fig. 11) and has been described previously as theoperating cam for the transfer bail 162. ther description of this cam isconsidered necessary.

The final cam in the group is disposed below the cam 101 and isdesignated by the reference numeral 241. This cam, as shown in Fig. 10,is contoured to impart gradual rotation to alever 242 pivoted on thestud 221, The lever 242 has a follower roll 243 which rides against thecam 241. As shown in Fig. 10, the radius of the cam 241 increasessteadily from minimum to maximum with an abrupt drop between theportions of maximum and minimum radius, and this causes the lever242.which is pivoted on the shaft 244, to rotate counterclockwisesteadily until it reaches its extreme counterclockwise position,whereupon it is restored rapidly to its extreme clockwise position. Abell crank lever which comprises a single arm 248 and two arms 249disposed in spaced horizontal planes and in substantially the samevertical plane is adjustably connected to lever 242 by a clampingengagement afforded by screw 241 extending through slot 246 in arm 248.Near their outer ends the arms 249 support the pivot pin 251. The pivotpin 251 serves as means for articulating to the bell crank lever arms249 a spacing pawl and a plurality of function performing bars. Cam 241and levers 242 and 249 serve, through the elements articulated to thelatter, as the means for efi'ecting character spacing and functionperformance through the cooperation of elements provided therefor.

Spacing mechanism The spacing pawl designated by the reference numeral256 is articulated to the pin 251 through a spring yield connectioncomprising slot 251, spring 258, and guide pin 259 (Fig. 9). The pivotpin 251 enters the slot 251 and is urged to the forward end of the slotby the compression spring 258. The pin. 259 is retained within the slotinside the convolutions of the spring 258 and prevents the spring fromescaping from the slot.

The normal movement of the'pawl 256 is reciprocatory, due to the rockingof the bell crank lever arm 249 by the cam 241, but if the movement ofthe pawl 256 is blocked as it may be under certain circumstances, thepin 251 may move within the slot and the spring 258 will take up themovement imparted by the cam and will restore the pivot pin 251 to theforward end of the slot 251 when the cam follower 243 has escaped fromthe highest portion of cam 241. The pawl 25'.) has at its opposite end aratchet engaging prong 261 which engages a ratchet 262 to impartcounterclockwise rotation thereto as the pawl is reciprocated, The pawlis spring biased into contact with the ratchet by a spring 263. Theratchet 262 is fixed to a rotatable carriage spacing shaft 264 whichcarries at its upper end a pinion 266 (Fig. 4) meshing with a rack 261con nected to the platen carriage 141. A step-bystep movement of thecarriage for letter spacing is effected by counterclockwise rotation ofthe The bar 223 has a further function which it performs only undercertain -'circum-" No furspacing ratchet 262 responding to thereciprocation of the spacing pawl 256. As the carriage positions towhich they are advanced by the pawl a Function mechanism The functionsof the hereindescribed printing apparatus, such as Line feed, Shift,fUnshift, etc., are selected in accordance with stop positions of thetype wheel, as determined by certain of the stop pins 96 which may beselected by the code discs 91, are conditioned for operation'by thelever 226 actuated by the print hammer operating cam 216, and areperformed by the lever arms 249 actuated by the spacing cam 241, Anyother desired functions may be selected, conditioned, and operated inthe same manner, and in the present embodiment of the invention, certainother .ones are so controlled, these functions providing for theoperation of electrical contacts for circuit control, such as renderingthe'transmi-tting mechanism inoperative, remotely controlling apparatusfor stopping the operating motor, and operating an audible signal, suchas a bell Other functions, particularly those which may conveniently beperformed with great rapidity, may be actuated directly from the printhammer operating cam 216, rather than from the less violent spacing cam241. In the present embodiment of the invention carriage return andspace suppression are so controlled.

Since, as hereinbefore outlined, the selection of functions iscontrolled in accordance with certain stop positions of the type wheel,means must be provided for effecting response of the functionconditioning or performing mechanisms. Such means has been provided onthe type wheel shaft 44 just above the gear 43 and comprises a pluralityof index pins or abutment pins 211 (Figs. 9 and 12) disposed in varioushorizontal planes and in various radial positions with respect; to thetype wheel. In certain horizontal p anes, only one index pin is found,whereas others contain several pins. The number of pins in a horizontalplane indicates the number of type wheel stop positions in which aparticular function is selected. Index pins in different horizontalplanes may be disposed in the same vertical plane, indicating that aplurality of functions may be selected simultaneously.

For cooperation with the index pins 211 there are provided a pluralityof superposed levers, the uppermost of which is designated 215 in Figs.9 and 12, pivotally mounted at their forward ends on a pivot pin 210carried at the rearmost end of lever 226 and extending through andsupported in horizontal slots in a plate 213. The levers are alignedwith the index pins 211 in the several horizontal planes, and eachcarries an abutment arm 212 extending leftwardly therefrom at a point-onthe lever toward which the their rearmost ends the lever 215 andcorresponding levers are provided with disc-like portions 214 disposedin notches in the forward ends of associated function levers which arepivotally mounted on the pivot shaft 216 and which will be identified byindividual reference numerals in the description of the several functionoperations.

Since the lever 215 and corresponding lever are articulated to the lever226 (Fig. 9), they undergo movement when the print cam 216 operateslever 226, and a lever such as 215 associated with a selected index pin211 moves differently than do those associated with unselected indexpins. The function levers to which the lever 215 and correspondinglevers are articulated by their disc-like portions 214 are biased totheir unoperated positions by springs 211, and they rotate in oppositionto the tension of such springs only when forced to do so. When the lever226 is actuated by cam 216, it carries the pivot pin 210 leftwardly asviewed in Fig. 9, and with it the forward ends of lever 215 and thosedisposed below it. If no index pins 211 are aligned with the abutmentarms '212, the lever 215 and corresponding levers pivot about theirdisc-like portions 214 and rock idly. If, on the contrary, an index pinis aligned with an abutment arm 212, it blocks the leftward movement ofthat arm, and becomes a fulcrum for the particular lever, thus causingthe lever to operate as a first class lever to actuate its associatedfunction lever and rotate the latter counterclockwise.

Certain of the function levers operated by the lever 215 andcorresponding levers areadapted to perform the associated function andothers are adapted to condition a function. The conditioning is effectedthrough superposed function performing bars, the uppermost of which isdesignated 280, pivotally mounted on the pivot pin 251 carried by thespacing cam operated bell crank lever arms 249. The function bar 280 andcorresponding bars are supported intermediate their ends inspacedhorizontal slots 219 in the vertical plate 213 (Fig. 1). They arereciprocated rearwardly when the bell crank lever arms 249 are rotatedcounterclockwise by cam 241 and they may rotate about the pivot pin 251within the confines of their supporting slots.

The uppermost index pin 211 and lever 215 are associated with therestoration of the platen carriage 141 to line beginning position, whichis accomplished by withdrawing the spacing pawl 256 and retaining pawl261 (Fig. 9) from engagement with the feed ratchet 262, whereupon thespring loaded drum 152 acts through the belt 151 to restore the carriageto its extreme right-hand position. The function lever to which thelever 215 is articulated is designated 281, and this lever is rotatedcounterclockwise when the uppermost index pin 211 is efiective upon itsassociated lever 215. The lever 261 carries upstanding pins 282 and 283located at the left and right of the spacing pawl 256 and the retainingpawl 265 respectively, and in close proximity thereto. When the lever28I is rotated counterclockwise, it moves the pins 282 and 283 to rightand left respectively and the pins rotate the spacing pawl 256 andretaining pawl 265 clockwise about their pivotal mountings-25I and 268respectively, to withdraw the pawls from engagement with the ratchet262. The carriage, being under noother restraint, responds to the forceexerted by the spring in the drum I52 and moves to its extremeright-hand position, rotating the spacing ratchet 262 clockwise as itdoes so.

It will be noted that the lever 28I is provided, near its rearmost end,with a notch in which are formed shoulders 286 and 281 (Fig. 12. Alatching lever 288 is pivotally mounted at 289 and is biased forclockwise rotation by spring 29I which has one end connected to thelever288 and the other end connected to the function lever 28I. When thefunction lever 28| is in its unoperated .or extreme clockwise positionas viewed in Figs. 9 and 12, the lever 288 is held in engagement withthe shoulder 286 by spring 29I. The rocking of the function lever 28Icounterclockwise to effect a carriage return operation permits the lever288 to escape from the shoulder 286 and to come to rest against theshoulder 281 whereby the function lever' 28l is latched in its operatedposition to maintain the pawls 256 and 265 out of engagement with theratchet 262. The purpose of latching the function lever 28l in theoperated position is to permit the carriage I4I, which; may bounceslightly as it comes into engagement with the dash-pot controlled leverI56 or the stop screw I54, to settle into its extreme right-handposition before the pawls are permitted to reengage the spacing ratchet262. Manifestly, the function lever 28I must be unlatched before anycarriage spacing operation can occur and an arrangement has beenprovided whereby the lever 28I is unlatched upon the next operation ofthe cam 2I6.

The arrangement includes a lever 292 (Fig. 9) which has a slot 293 whichis entered by a screw 294 carried by lever 288. The slotted engagementbetween lever 288 and lever 92 provides a yielding connection, and aspring 296, which has one end connected to the lever 292 and the'otherend connected to an extension of the lever 288, tends to rotate thelever 292 in a counterclockwise direction which is prevented by a lug291 carried by a fixed plate 295 against which the lever, 292 rests.Since the spring 296 is disposed between the lug 291 and the screw 294,the extreme left end of the slot 293 abuts against screw 294. A rod 298is slidably supported in the lug 291 and in a portion 299 of the frameof the mechanism and occupies the same horizontal plane as the lever292. The rod 298 slides freely within frame member 299 and the lug 291and is urged to its rightward position by the lever 292. The lever I56which is articulated to the dashpot plunger rod I58 carries aneccentrically mounted adjustable abutment 30I in alignment with theright-hand end of the rod 298. The abutment 30I is similar to thepreviously described abutment 230 and is below the pivotal mounting I51of the lever I56 so that it is moved toward the rod 298 as the carriageI4I rotates the lever I56 clockwise at the completion of a carriagereturn operation. When the lever I56 comes to rest in its extremeclockwise position at the conclusion of the carriage return operation,

its abutment 30I moves the rod 298 leftwardly. a distancelsufficient tocause it to rotate the lev "292.clockwise and position the forward endoe that lever inalignment with the rod 223 articu f lated totnbellTfranklleyer 2|9. Lever 292 will]? occupythisposition as long as thecarriage MI is in its extreme right-hand position and upon the nextcounterclockwise rocking of the bell crank lever 2I9 by the box cam 2I6,rod 223 will be reciprocated rearwardly and will communicate itsreciprocating motion to lever 292, which will cause the latching lever288 to be rotated counterclockwise out of engagement with the shoulder281 and into engagement with the shoulder 286. The function lever 28Iwill thus be restored to its unoperatecl position and the pawls 256 and261 will reengage the spacing ratchet 262 in preparation for normalspacing operations. The slotted mounting of lever 292 provides a yieldconnection which may, under certain circumstances, operate yieldingly onaccount of a blocking condition. The carriage, I4I may, particularly ifit travels through only a short distance in returning to its extremeright-hand position, reach that position while the bar 223 (Fig, 9) isbeing operated by the cam 24I and before the bar has been withdrawn toits foremost position. Under this condition the rod 298 might jam theforward end of lever 292 against the right-hand face of operating bar223, whereby the rod 298 might be prevented from traveling its normaldistance and the carriage I4I be prevented from assuming its extremeright-hand position. The slotted connection permits the lever 292 to befully moved by the rod 298, even should the forward end of lever 292 beblocked by bar 223.

Shift and unshift mechanism It will be convenient to postpone thedescriptionof the functions associated with the multiple sets of indexpins occupying the second and third positions from the top on the typewheel shaft 44 until the remaining functions have been described, thereason for such postponement being that the description of the functionsthus passed over will be more readily understandable. Accordingly,attention is directed to the function lever 302 (Fig. 12) carried by theshaft 216 in alignment with and articulated to the lever 305, which isassociated with the index pin in the fourth level from the top. Thefunction lever 302 is associated with the shift operation by means ofwhich the type wheel is shifted to remove one of the annular sets oftype pallets from alignment with the print hammer I36 and to bring theother set of type pallets into alignment therewith. The lever 302 doesnot perform the shift function but merely establishes a condition as aresult of which the function may be performed, and to this end it isprovided with a projection 303 which'occupies the same horizontal planeas the bar 280. This bar has its rearmost end disposed slightly to theleft of a latching projection 304 of a latching lever 306 which ispivotally mountedon shaft 268 (Fig. 9) and is biased in a clockwisedirection by spring 3 I0. All levers corresponding to lever 306 arebiased clockwise by springs 3I 0 and are limited by abutment againststud 300 (Fig. 9). Upon the selection of the index pin associated withthe lever 305, and upon the operation of that lever, the lever 302 isrotated counterclockwise similarly to the previously described functionlever 28I, and

through its projection 303 it imparts a. clockwise rotation to the bar280. The latter bar, in rotating, moves to the right of latchingprojection 304, and at the same time it moves rearwardly due tooperation of bell crank lever arms 249 by cam 2l6, and becomes latchedin its clockwise position.

The bar 280 carries on the right side thereof a projection 301 which isdisposed in alignment with the lower end of a shifter lever arm 308(Figs, 7 and 8) to which it imparts a counterclockwise motion as viewedin Fig. '7 as the bar 280 is reciprocated rightwardly due to continuedcounterclockwise rocking of the bell crank lever arms 240 by the cam 2.:The shifter lever arm 308 is one arm of a bell crank lever pivotally.

mounted upon the previously described pivot shaft 232 and having itsother arm 3H extending rearwardly of the printer. The lever arm 3| l isbifurcated at its outer end and hasdisposed in the bifurcation a pin 3l2carried by arm 313 of shifter frame 3. The frame'3l4 is mounted on shaft232 by means of slot 3l6 so that it may be raised and lowered verticallyto lift and lower the type wheel through its horizontal arm 3I'l (Figs.1 and 4), which is guided on guide screw 3I5 and which engages the typewheel hub I23. The operation of the lever arm 308 upon the shifter frame3l4 is to lift the latter through the articulation of the lever arm 3 tothe frame 3|4 by virtue of the pin 3l2. The frame 3 carries a pivotedspring loaded detent 3I8 which has notches at the lower end thereof,either of which may engage a bushing 3l9 on the shaft 232 to maintainthe shifter frame 3l4 in a position to which it is moved. A spring 3l4'(Fig. 1) counterbalances the shifter frame 3 and type wheel ll, and thusequalizes the forces required to effect shift and unshift operations.

Referring again to Fig. 12, it will be observed that a function lever32I similar to the lever 302 and having a projection 322 is pivotallymounted on the shaft 216 below the lever 302 and in articulation withthe lever 325. Two angular-1y spaced index pins 21! are disposed in thesame horizontal plane as the levers 32| and 325, which indicates thatthere are two stop positions of the type wheel shaft which will resultin operation of the function lever 32L Lever 32! is associated with theunshift function of the printer. An operating bar 320 is aligned withthe function lever projection 322 and is also aligned with a latchinglever 323 below and similar to the latching lever 306 and provided witha latching projection 324. The operating bar 320 is articulated to thepivot pin'25l directly below the operating rod 280 and is provided atthe side thereof with a projection 326 (Fig. 7) which, when the rod islatched in its extreme clockwise position by the projection 324 of lever323, is disposed in operating alignment with a lever arm 32! similar tothe lever arm 308 but necessarily slightly longer than that lever arm.The lever arm 32'! constitutes, together with a forwardly extending arm328, a bell crank lever pivotally mounted upon the pivot shaft 232. Theouter end of the lever arm 328 is bifurcated similarly to the lever arm3| l and engages a pin 329 carried by a forwardly extending arm 33! ofthe shifter frame 3|4. When the lever arm 32! is rocked incounterclockwise direction due to movement of the projection 326 of theoperating bar 320, the lever arm 328 will also be rockedcounterclockwise and will move pin 329 downwardly, whereby shifter frame314 is moved downwardly to effect an unshift operation. It is apparentthat the leverarms 308 and 321 operate oppo-' sitely and simultaneouslyso that as one effects movement of the shifter frame, the other isoppositely rotated and presented in position to be next effective in theshifting of the shifter frame 3.

It was previously mentionedthat the unshifting operation conditioned bythe function lever 32! and performed by the bar 320 may be selected foreither of two stop positions of the type wheel shaft, as indicated bythe presence of two index pins 21! in the same horizontal plane, eitherof which may be effective. One of the pins is associated with theunshift signal and is presented in operating position when the signalcombination assigned to unshifting is received. The other pin ispresented in operative position when that code combination isreceivedwhich is assigned to spacing, for the reason that it has been found thatin many instances printing following a blank spacing operation is to beeffected with an unshift condition of the printing mechanism, and it istherefore convenient to effect the unshifting automaticallysimultaneously with the spacing, thus obviating the transmission of aseparate unshift code combination.

Line feed The single index pin immediately below those assigned to theunshift function is associated with the line feed function which is afunction accomplished by rotating the printing platen I39 to advance asheet or web of paper upon which printing is to be effected through adistance sufficient to present a line of blank paper to the printingposition. The selection of the line feed index pin and the rocking ofthe lever 335 Fig. 12) against the pin causes the operation of afunction lever 332 which is similar to the levers 302 and 32I and whichhas a projection 333 for operating the associated function performingbar 340. A function operating lever 334 is pivotally mounted below thelatch lever 323 on the pivot shaft 268 and is similar to that leverexcept that it has operative connection with the line feeding mechanism,as will be described, and is therefore a true function performing lever,and it has no latchingprojection. A separate latching lever 336 isprovided which is also pivotally mounted on the pivot shaft 268 andwhich has at its righthand end a forwardly projecting arm 33! whichterminates in an upwardly turned projection 338 which occupies aposition with, respect to the lever 334 corresponding to the latchingprojections 304 and 324 of levers 306 and 323 respectively. The lever336 is spring biased in a clockwire direction by spring 339, movement inthat direction being limited by the stud 300 (Fig. 9), and it is capableof counterclockwise rotation independently of the lever 334 to permit itto be cammed in a counterclockwise direction by the operating bar 340and to return to its extreme clockwise position where its latchingprojection 338 latches the operating bar 340 in conditioned position.When the function bar thus latched is reciprocated rearwardly in themanner common to all of the function performing bars, the lever 334 isrotated counterclockwise about the pivot 268. The lever 334 has securedthereto at its right-hand end by screw 3 a link 342 which is providedwith a slot in which is disposed the operating arm 343 of a line feedbail 344. The bail 344 (Figures 4 and 21) is pivotally mounted insuitable brackets 346 on the rear

